The present invention relates generally to printable and electronically imageable clear and opaque pressure sensitive adhesive (PSA) coated cellulose substrates for tapes and labels that have a novel print receiver engineered to provide multi-functional print properties of conventional printing techniques as well as variable imaging employing wet or dry toner technologies that require heat to fuse the toner. The substrate is preferably provided with a lay flatness release liner backing that will lay flat through the various printing and imaging processes.
An example of where this invention could be used is a laser printable-pressure sensitive adhesive coated label that is first printed with fixed information using conventional flexographic printing techniques before the label is die cut into sheets of discrete labels for subsequent laser printing of variable information. These labels are made from a single ply of a thin clear cellulosic film substrate coated with a pressure sensitive adhesive. This substrate, for example, could be used in bar coding and price marking applications replacing polyester films or vinyl films mounted on a heavy release liner that acts as a heat sink in the current art. Vinyl films will melt if they jam in the fuser of a laser printer.
Most preferably, the invention relates to a novel single ply substrate that uses a low cost clear or pigmented white heat resistant cellulosic film substrate, a pressure sensitive adhesive, lay flat release liner and a multi-functional print receiver coating. In addition to providing conventional print reception, the receiver coating also provides and helps maintain the electrical properties through all processing needed for toner electrostatic printing, also known as laser printing.
The labels of the current invention can be used as lower cost heat resistant film labels in applications where a heat resistant label is needed, especially in variable imaging processes such as laser printers employing heat fused toner technology. Printed labels comprise an important form of communication for permanent and temporary labeling of various items. Labels are commonly used to convey information in a wide range of applications. While this invention is not limited to any specific market area that would use a heat resistant label and this disclosure is in no way meant to be limiting, shelf labels used in the retail environment familiar to all will be used for illustrative purposes.
For example, in the retail environment, labels are commonly applied to product displays to identify objects and to convey information about those objects to customers such as pricing, product identification, sale details, etc. Product information tends to be dynamic in this environment and product offerings and pricing undergo frequent changes. Point-of-sale product labeling is often changed by applying new labels to the edge of shelves on which the products are displayed. Such shelf labeling is a significant part of the labeling activity in commercial retail establishments and large numbers of labels are used today in retail outlets for shelf edge price marking and promotional labels called shelf talkers. The typical retail market includes aisles of shelves on which identification and price labels are affixed using a pressure sensitive adhesive on the back side thereof which forms a removable bond with the shelf edge. A shelf talker is a special type of product label used for promoting brand identity, units of measure, price comparisons, and special sale pricing and promotions. The shelf talker is usually larger than the shelf label, and is used in addition thereto for increasing the visibility of the particular product being promoted. Shelf talkers are usually made of clear film that is placed over the price marker label and is designed to be removable from the base price label and shelf edge the contact clear label is applied over.
Labels with variable imaging are typically provided in groups of similar die cut size on individual sheets for collectively printing the desired information thereon. Fixed information, such as store identification and product graphics can be pre-printed in large quantities of the sheets in a suitable manner during the production of the die cut labels and variable imaged at a later time or die cut blank labels can be produced that are imaged with fixed and variable information at a later time. Variable information is printed on a common sheet such as the specific product, size, price or promotion information may be locally printed at a service bureau or distribution center that will distribute the labels or they can be printed on-demand at store level using laser, thermal transfer and direct thermal printers.
Due to their typical temporary applications and disposability, shelf labels must be easy to produce, install, remove and be durable to withstand the rigors of the application such as cleaning with various hard surface cleaners. Cost is always a significant factor for the substrate material. Lighter weight functional substrates are preferred for reduced shipping and distribution costs. As many prices and promotions change weekly, new shelf edge labels and shelf talkers are typically sent out by courier. Couriers are now migrating to “Conventional Packaging” where you pay a fixed price for a certain size package with fixed dimensions and an upcharge for excessive weight. A thinner composite of face stock, adhesive and liner will allow for more labels in a box and assist in reducing distribution costs under the new dimensional packaging pricing now used as a standard by most courier services. Because of the sheer volume of these types of labels that are consumed, an environmentally sustainable substrate is preferred.